Objective   To investigate the effect of transarterial infusion (TAI) chemotherapy on estrogen receptor (ER) and progesterone receptors (PR) expression in breast carcinoma tissue.    Methods   Samples of 81 patients with breast carcinoma were selected in this study. ER and PR mRNAs levels in the samples were determined by RT-PCR. Immunohistochemistry was employed to measure ER and PR expressions in different samples before and after TAI chemotherapy. Western blotting was used to assay ER and PR proteins level in the samples before and after the chemotherapy.    Results   RT-PCR results indicated that ER mRNA level was increased in 43 cases (53.1%) and PR level in 33 cases (40.7%). Meanwhile

both ER and PR mRNAs levels were increased in 25 cases (30.9%). Immunohistochemistry results showed that ER level was up-regulated in 35cases (43.2%)

and PR level in 21 cases (26.0%). Both ER level and PR level were up-regulated in 16 out of 81 cases(19.8%). Western blotting also suggested that the both proteins levels of ER and PR were up-regulated in some patients after the chemotherapy.    Conclusion   Transarterial infusion neoadjuvant chemotherapy affects the mRNA and protein level of the hormone receptors

which facilitates the subsequent killing effect of chemotherapy on tumor cells. ER and PR expressions should be determined after the transarterial infusion chemotherapy

which might provide a guide for the subsequent treatment and prognosis.